Symbol

Rh

Atomic Number

45

Atomic Mass

102.9055

Family

Group 9 (Viiib) Transition Metal; Platinum Group Pronunciation

RO-dee-um

Overview

Rhodium is considered to be a precious metal. A precious metal is one that is rare and valued. Other precious metals are gold, silver, and platinum. Rhodium is also classified as a member of the platinum group of metals. The platinum group includes five other metals that often occur together in nature: ruthenium, palladium, osmium, iridium, and platinum.

Rhodium falls in the center of the periodic table. The periodic table is a chart that shows how chemical elements are related to one another. Elements in groups 3 through 14 are called the transition elements.

Rhodium was discovered by English chemist and physicist William Hyde Wollaston (1766-1828) in about 1804. He discovered the metal in an ore that apparently came from South America. The rhodium compound he first discovered was a beautiful rose color.

Rhodium is...